Efficient radio resource allocation is important in the design of wireless communication systems. As the number of multimedia sources being channeled through wireless systems increases, the demands palced on the wireless access node becomes incrisingly challenging. Currently, four traffic classes are defined for packetized service: controversional (e.g. throughput, delay, telephony) streaming (e.g. radio broadcast over the internet), interactive (e.g. web browsing) and background (e.g. email). Wireless systems are required to uphold stringent quality of service (QoS) requirements (e.g. throughput, delay, signal loss) despite the fact the wireless systems, packet-level limited compared to wireline channels. In wireless systems, packet-level scheduling and radio resource allocation can present problems in meeting QoS requirements for all users (mobile) in the system. Traditional wire-line schedulers such as first-come first serve (FCFS), priority queuing or weighted-fair-queuing (WFQ), are not aware of the radio conditions (e.g. channnel gain values) and thus making scheduling decisions without talking radio conditions into account. For example, if mobile A is transmitting on a strong channel and mobile B is transmitting on a weaker channel, traditional wire-line schedulers would not take this information into account. If instead, transmissions are prioritized based on channel conditions, it is possible to improve system throughput. Thus, utilizing a scheduler with knowledge of the radio conditions produces a more efficient system.
Efficency is not the only concern in a commercial system. The system must also be designed to ensure that resources are fairly arbitrated among the various mobiles so that each user can meet its QoS requirements. Some schedulers, that are cognizant of the channel conditions and that attempt to maximize efficiency while maintaining some degree of fairness in the arbitration of resources, have been proposed. However, none of the proposals provides a means to change the relative emphasis between system efficiency and fairness of allocation as the need arises.
Thus, there is a need for a systematic and flexible means to strike different trade-offs between system efficiency and fairness of allocation.